Rocket projectile



May 5, 1959 J. M. ALEXANDER ETAL 2,884,859

ROCKET PROJECTIIJE 8 Sheets-Sheet 1 Filed Nov. 4, 1955 AGE y 1959 J. M. ALEXANDER ErAL 2,884,859

ROCKET PROJECTILE m mp T @QQ m 8 J8 A my M 8 r m wow m 1 J 4 m N m m J. M. ALEXANDER ET AL Mays, 1959 U ROCKET PROJECTILE 8 Sheets-Sheet 3 Filed Nov. 4, 1955 INVENTORS JAM/33S M. )SJEXANDER R 'I-H MEN 6 V AGENT May 5, 1959 J. M. ALEXANDER ET AL ROCKET PROJECTILE 8 Sheets-sheaf; 5

Filed Nov. 4, 1955 INVENTOISER 7 :RGENT y 1959 J. M. ALEXANDER ETAL 2,884,859

ROCKET PROJECTILE 8 Sheets-Sheet 7 Filed Nov. 4, 1955 IN VEN TORS May 5, 1959 J. M. ALEXANDER ET AL 4,

ROCKET PROJECTILE Filed Nov. 4; 1955 8 Sheets-Sheet 8 NW UHF U i cd tatcs Pat This invention relates generally to artillery projectiles "and more particularly to rocket assist types'of projectiles of the major caliber fields such as the 5.7 mm. through 'the 280 mm. or any such "other caliber as the Ordnance Corps of the U. S. Army and U. S. Navywould consider practicable and is a continuation-impart of" our application'Serial Number 461,358, now abandoned, ,filed October 11', 1954. p I j v In the manufacture of artillery ammunition, it is a recognized fact that the longer the ranges, the higher the terminal velocities, the greater the striking forces and detonating forces the more potent the weapon becomes. Present day ammunition has reached its current ranges and high muzzle velocities :by increasing the breech or chamber pressures of the gun by utilizing .a longer and larger cartridge'case, so that more of a propellent charge can be used; These breech or chamber pressures have about reached their feasible limits as the increases in the pressure to reach these higher velocities, has reduced the barrel life of the gun to a minimum.

Moreover, in the design and manufacture of small caliber artillery ammunition, it has not been possible to develop a proximity or even a time delay fuse for the smaller sizes. It is definitely desirable to be able to fire the small caliber projectiles with contact fuses as antiai'rcraft projectiles but thistype of, ammunition is very hazardous and hence, not desirable for usei-n or around crowded areas or under conditions in which-these projectiles in their normal trajectory would fall within the limits of our own troop concentrations. it would be extremely advantageous to be able to fire, as anti- 'aircrait defense fweapons, ,a projectile of small caliber that would have an extre'melyhigh rate of climb and be safely armed with a contact fuse, yet armed so as to explode automatically at or near the topof its trajectory. Thusthe present invention insures that any small caliber ammunition thatfails to find atarget in its trajectory,

will disintegrate through self detonation to eliminate the hazard of falling high explosive missiles. I

Accordingly, the chief object of the present invention is to provide an improved rocket type projectile haying Another important object ofthe present-invention is to I i h longer ranges, higher terminal velocities, more ballistic provide an improved rocket type projectile having a fuel which acts as both a fuel for the main propellent and the bursting charge. 1

Another objective of the present invention is to provide an improved rocket type projectile having a single or dual propellent in which the fuel orfuels areaccurately metered by centrifugal force through a nozzle to a rocket combustion [chamber to provide the main propulsive force for the projectile after it leaves the gun as well as rotational stabilizing forces therefon.

Afurther important of o I o improved rocket type projectile in which the fuel or fuels the invention is to provide an 1 2,884,859 Patented May 5, 1959 er C v 2 I v and explosive chamber is located on the central axis thereof so as not to upset the rotational balance of the projectile while in flight. v a A still further important object of the invention is to provide an improved rocket type projectile which is susceptible of ready and economical manufacture while being of far superior performance characteristics.

Other objectives and advantages of this invention will become apparent during the course of the following description.-

In its broadest aspects, the invention contemplates a rocket assist type projectile utilizing either a single or dual propellent that becomes operative only after the projectilehas been fired from the gun, the propellents ofwhich could be used either as a propelling charge or as abursting charge or both so as to safely and economically obtain longer ranges, higher terminal velocities, greater striking anddetonating forces. Y

'- ln the drawings we have shown several modifications of the basic forms of the invention. In these showings:

*"Figure 1 is a central, longitudinal sectional view of one form of the invention; Figure 2 is a central, longitudinal sectional view of the rocket' motor showing its combustion chamber, its exhaust or jet nozzle and one of the directional acceleration holes or smaller jet nozzles;

Figure 3 is a rear elevational view thereof;

Figure 4- is a vertical transverse sectional view of the invention, taken on the line 4-4 of Figure 1, parts being shown in elevation;

slightly modified form of the invention;

Figure 10 is a central longitudinal sectional view of another slightly modified form of the invention.

Figure 11 is a central, longitudinal sectional view of one form of the invention using a single mono liquid propellent with an armor piercing war head;

Figure 12 is a transverse, sectional view thereof taken on the line 12- 12 of Figure 11 showing the agitator placed in the lbroached slots;

Figure 13 is a view similar to Figure 11 but showing a dilferent type of armor piercing war head;

Figure 14 is a central, longitudinal sectional view of another form of the invention using a single liquid propellent as both a propellent and a bursting charge and utilizing either a timed, contact, or a proximity fuze;

Figure 15 is a transverse, sectional view thereof taken on the line 1515 of Figure 14 and showing the agitator placed in the broached slots with the explosive limiting spacer in position; i Figure 16 is a central longitudinal sectional view of another form of this invention using a single liquid propellant as both a propellant and a bursting charge and utilizing either a timed, contact, or a proximity fuze;

' Figure 17 is a transverse, sectional view thereof taken on the line 1717 of Figure 16 and showing the explosive limiting spacer and the curved agitator in the broached slots;

Figure 18 is a central longitudinal, sectional view to an enlarged scale of the form of the invention shown in Figure 11 but modified for use with a dual propellant;

Figure 19 is a transverse, sectional view thereoftaken on the line 19-19 of Figure 18 and showing the propel- 3 lant chamber locked in two of the broached slots of "the projectile body; p I

Figure 20 is a central, longitudinal, sectional view of the form of the invention shown in Figure 13 but modified for usewith a dual propellant;

Figure 21 is a central, longitudinal, sectional view or the form of the invention shown in Figure 14 but modified for'use with a dual propellant; and

Figure 2-2 is a central, longitudinal, sectional view of the forrnof the-invention shown in Figure 16 but m'o'dified for use with adualpropellant.

The -present invention may be applied to projectiles of various kinds and types, including armor piercing, high explosive, shells, bombs, and torpedoes and the initial flight of such projectiles may be initiated in any suitable manner. In the case of light artillery ammunition, the projectile may be assembled in the usual way of crimpingthe cartridge case, carrying the usual powder charge, to the projectile. In heavy or major caliber ammunition the projectile may be separate from the powder charge or the cartridge case.

The invention utilizes the rocketprinciple incorporated into and becoming an integral part of an artillery projectile for the purpose of increasing the range, the terminal velocity, the striking and the detonating force of the projectile after it has been fired from the gun. The-rocket motor utilizes liquid fuels which in some instances'ar'e liquid explosives that contain a flash back preventative so that it cannot become a sel'f detonating projectile, I

The use of the liquid fuels 'was dictated because-elf higher power, more thrust, better metering, better I control on their burning, greater facility in loading, and availability of a wider variety. In 'the'single mono-propellant letranitroinethane 'and nitromethane, toluene,- octane,

dodecane or CO gas makes a very powerful explosive as well as an extremely powerful propellant. The initial rotational velocity imparted to'the projectile by the 'rifii'ng grooves in the gi'ln barrel to spin and stabilize the projectile while in free flight is also used to develop 'centrifugalpr essure to feed and meter the fuels to the rocket motor from the projectile body. This centrifugal pressure furnishes the pressure differential necessary to .feed and meter the fuel at controlled and .predeterminable rates through the metering no'zzle passages to the rocket combustion chamber. v

In some instances wherefa dualepropellantfis 'useiythe ce trifugal pres ure is also used t mi as well teed a dm'eterthe-difierent fuel-s'to the combustion chamber.

' The controlled burning force whichwill accelerate the projectile in ever increasing velocities until a predeterminable amount of fuel has been expended. As this amount is reached, the remaining fuel will uncover the metering passages and the burning or detonation wave will travel back up stream to deton'ate the balance of 'th'efuel in the body of the projectile unless 'a flashback preventative is used in the mono projillailt.

A time delay or proximity fuse used in the larger c'aliher ammunition will operate i the usual way except that thisprojectil will have a much higher terminal velocity. When used with an "armor piercing heed, the projectile, upon reaching the targetwill start penetrating, the rotation will slowdown, and the detonation wavewill travel 'iips'tream and c use th'e projectile to explode, drivin the armor piercihg head in further or, in the event that the armonpiercing head has alreadypehet'rated-the exploding of the remainder of the charge hieytake place after "the projectile has passed the armor barrier.

In all calibers, provision is made to accelerate the rota- 5 tional velocity imparted by the rifling during firing b'yfi'he hiaiiles rseof auxiliary di ectional rotational holes orfje't drilled concentrically about'the main jet 'hoiz'le the ro lr'etniotor. These auxiliary holes will notonly aintain but-Will increase the rotatiohalvelocit cftheproof th f el in the cpn lh siiena chamber delivers a predeterminable amount of thrust or 4 ie'cti'l-e' so th'at'the longer and heavier projectile will be ballistically stable in flight.

When used in major caliber ammunition in conjunction with a time delay or proximity fuse a flash back preventative is used in the mono propellant so that the balance of the fuel remaining unburned will then become a liquid explosive that will be initiated by the different types of fuses.

The propellants used in the forms of the invention disclosed in Figures 11- 1 7 inclusive are also of the mono propellent type as hereinbefiore described but utilize a hash back preventative or inhibitor so that "the projectile will hot be self dton'atiii'g'.

The rocket fuels used in Figures 1-17 inclusive of this invention are of "the niche propelle'nt type which furnish and contain all of the elements necessary for combustion within the same molecule. These liquids are not only rocket fuels but are also liquid explosives. Examples of such liquids are tetranitroihethane, toluene, trinitro- 'n l' he, hitfohl'eth'aiie, 'ilitioethane, l-hitroprop'ane, 2- "hi opropahe, l,1-dinitr propahe, 2,2-dihitropr'opah 1,2- d'ihitropro ahe, 1,3 dinitropr6pane, Ll-dinitroethane,

'1,l,'l-rrihitr o ropane, 'l,2,3-'aihitropropahe. The fuel and explosi' e "chamber is located on the central axis of the proiectile bedy so that the burning of therocket fuels "will not upset the rotational balance an.

of theprojectile while in I ctile out of the gun her, its an anon beihg started by ggrooves 1n the barrel. A trace; mixtiireor er w ich is compacted in the combustion chamber the rocket ino'tor 'is ignite-d te fu sh an additional o fthrnst'which "may he timed to a predeterlimit and the projectile clears the gun barrel durin interval.

In the invention,

a fusible "sea-ling disc is employed 'tosealfthje mj ete'rihg ho'z'zlepasseges between the tracer the fuel in the body of the'p'rojectile and upon inelting "of the'eisc by the burning of th'e'tracer builtmp centrifhgal pressuie of the rotationfnel forces itthrongh he metering passages into the burning mixture in the rocket "no'Z'zle'where it is als' 'o ignited. The g'as'e's if" the bhrhihgfnel are expelled under high pressure th n"""zl'e and the obliquely leia'tion holes to'prep'el j "d'de'd"rotatiohalvelocity. A U rock t "motor continues jsuc time as the f el almost expended at which passages will be uncov red and the burning of the fhe'l wil'l thereupon travel back upstream through fthe'tue'l metering passages and cause the halanceoi the fuel inihe fuel chamber to explode, except in the fo'r'ir'is 'of -the invention shown in Figures 1 1-17 inclusive wherein flesh backprevehtative is incorporated in the fuel which thus can explode onlyon contact.

lnere'r in' totherawings, nume al '12 designates a whole the'projeotile comprising the present invention which is adapted r use as artillery ammunition "andfis assembled with a cartridge case '0 having the usual initial propellent char e I The projectilell includes an elongated tubiilar'bddy 15 etstjro heatedresistants teel alloy, "21 copp'er'r'iflin i d 18 h abut the canridge'case C, an external shoulder 17 having 'il'l'te'iior' threads for connection "with an adapter 18 having a chamber 19 terminating at its right and in a threaded ortion for connection with a head iii-ruse 20. I I rhe' iiiterioi 'ftheprojectile Body is includes a rocker "more; a fusible sealing d 4, a metering noz ile :25 dai efgit or inthe liqmd'fuelspace or chamber efined between the ozzle 2'5 and the adapter '18. r t tor 2o ra to impart the rotational velocity or the projeottlewhile in to theliqiiid fuel in the chamber 27 audit is important that the fuel be equally distributed throughout thechamber 27 at all times so as not to upset the rotational balance of the projectile. To this end the blades of the agitator (which may be greater or. lesser in numberas long as they are 'augularly 'displaced'equally) are each, provided with a plurality of longitudinallyspaced ports 28. This arrangement ensures that no fluid fuel can be trapped on one side of the bladesand not drain equally with the 1 others.

"Theagitator 26 is fixed in positionwithin the body .15 byslidingthe edges of the blades into angularly spaced broached slots 29 formed in the body. The blades thus divide the chamber 27 into compartments having free communication by virtue of the ports 28. .Additional communication between the compartments is had at the ends of the agitator 26 due.to'the slope of the blade and .edges inwardly and toward the left asjseenin Figures 1 and, 5-to define, in eifect, cones of revolution whose apices are to the left to space the blades from the passages 34 andithe thin wall 30. 1 i

,More important, the inclined bladeedges described not only aiford free'access of fluid fuel from the com- :partrnents in the chamber 27 to the-apertures in the gnozzle 25 but also afford direct access atthe right end of the chamber to a frangible wall 30 closing the left end .of the'adaptor chamber 19 which may contain a detonator such as tetryl. 1 7 2 Themetering nozzle 25 (Figures 1, 7 and 8) comprises La thick disc having a forwardly directed annular flange 33 which bears against the end edges of the agitator 25 and'clamps it against the rear face of the adaptor 18. .The nozzle is provided with-a. plurality of angularly spaced, longitudinally extending fluid metering passageways 34 whose rear apertures 111613105811 by the sealing ,disc24 which is clamped between the nozzle 25 and the rocket motor 23. t Thetocket motor. 23 includes a combustion chamber .35 in which a powder-charge or solid propellant 36 of the restricted burningtypeiscompacted. The combustion ,chamber terminates in a main exhaust jet nozzle or,opening 37 and a pluralityof angularly'spaced, canted, direc- .tionalgacceleration.- holes,or' jets 38.. The motor 23 is provided with aperipheral groove 39. which cooperates ..with a rib on the projectile. body 15 to hold the rocket motor in place. It is further securedtherein'bya roll crimp 40 of the end of the body 15 over the end shoulder 41 of the rocket motor 23: r

1 Itis' believed to be readily apparent that in the firing ofthe projectile 12, the propellent charge 14 in the cartridge case C will ignite the compacted solid propellant 36 in the rocket combustion chamber 35. The burning propellant 36, however, will not melt the seal 24 until the 1 projectile -12 has left the barrel of the gun and is in :flight'. -When the seal 24melts, the centrifugal pressure resulting-from the. rotational velocity of the projectile 1 t0 the barrel rifling and the added rotational thrust obtained by the canted jets 38) will result in liquid fuel being metered through the passages 34 in the nozzle 25 ,tothe Combustion chamber 35 from thefuel chamber 27.

The burning of the liquid fuel inthe combustion chamber 35 provides the main acceleration of the projectile after it leaves the gun barrel or'tube and continues until I l in'ed herein, the uncovering of thefuel passages by the jless en'ed 'fuel in the chamber 27 permits the burning to bjack up through the fuel passages 34 and ignite the "balance vof the fuel' in thechamber 27 to explodethe "projectile15. 4 i i If the target is struck by the projectile before its selfexplosion or detonation, the fuse 20 and the tetryl in the adaptor chamber 19 will effect detonation. As shown in Figures 9 and where the adaptors clamp the head or fuse against the agitator 26, it is not essential that the the fuel in the chamber 27 is almost expended; As ex adaptor 18 include achamber 19 fora-detonator such as tetryl. r r

,:In Figure 9, We have shown a smaller caliber projectile '15 wherein theposition of the rifling band 16 is moved rearwardly on the projectile for longitudinal balance purposes whereas in Figure 10, the band .16 is moved forwardly along a larger projectile. As shown in Figure 9, the right ends of the agitator blades are curved forwardly as at 44 to allow the unexpended fuel free communication and access to the rearface of the fuse so as to eflect proper detonation of the projectile upon its striking a target and to enable clamping contact of the agitator by the head, the curved plate ends being unnecessary in the larger projectile of Figure 10.

It will now be readily apparent that the forms of the artillery projectile comprising the present invention. as shown in Figures 1l0 inclusive willautomatically explode or explode oncontact with a target, uses asingle main propellant which is also the explosive charge, will not explode until after leaving the barrel of a gun, and

will have, a longer range,- a higher terminal velocityand a greater striking force than other known projectiles, While also lengthening the life of. a gun barrel tremendously.

The propellants-used in the forms of the invention disclosed in Figures 11-17 inclusive are also of the monopropellant type as hereinbefore described but utilize a flashback preventative or inhibitor so that the projectile will not be self detonating. These forms of the invention are of the higher calib'ers, and in structure and operation are similar to the projectiles disclosed in Figures l'--l0 inclusive.

These forms 112 of the invention also comprise a body portion 115, a rocket motor 123, a fusible sealing disc 124, a metering nozzle .125, and a fuel agitator 126 in the fuel chamber. 127. The'chamber terminates in an adaptor 118 for a war head 120. Figure 11 differs from Figure 13 only in the use of. a different typeof armor piercing war head and adaptor connecting it to the body of the projectile 112. r

It will be appreciated that if either of the disclosed projectiles contacts an armored barrier before all of the fuel in the chamber 127 is consumed as a rocketpropellant, the unconsumed portion will become a liquid explosive detonating on impact.

The embodiment of the invention disclosed in Figures 14 and 15 is similar to that of Figures ll-13 but difiers in the inclusion of. a transversely extending, spacer disc 121 formed integrally with or fixed to the agitator 126. The disc 121 is provided with an aperture 122 positioned adjacent to but spaced from the axis of the projectile in each of the sections of the fuel chamber 127 formed by the agitator 126. v

The apertured spacer disc 121 is an important feature of the invention in that it retains a predeterminable (by the spacing of the apertures 122 from the axis) amount of the liquid explosive or fuel in the forward part of the projectile to provide the bursting charge. The spacer disc also braces the agitator 126 and as shown in Figure 16, a plurality of spacer discs 121 are employed to brace the agitator as the weight of the liquids in the projectile runs about 78 lbs. The need for either such bracing or heavier agitators is appreciated when considering the stresses involved in accelerating 78 lbs. to 7,200 r.p.m.

. A000 of a second.

In order that none of the propellant fuel be trapped between the discs, all but the one at the front are provided adjacent their peripheral edges with a plurality of angularly spaced drain apertures 131. The agitator blades of the embodimentshown in Figures 16 and 17 are .qnined I amount -of a chamber of the rocket motor 123' contains a predeter- -solid propellant -which burns at "a rate of from'2 to 10 inches per second. This propellant is'one of the-solid rocket propellants such as: 'NDRC National Defense Research Committee, Galc'it Series; Guggenheim Aeronautical Laboratory, Galiforn'ia 1nstitute of Technology; ballistic, smokeless or black pow.- der and due to its burningcharacteristics,acts'as a delay clement. The operation of the projectiles --disclosed in :Figures ll-1'7 is, of course, the'same' asset forth -in .connect'ion with Figures 1 to 10 in Figures 1 8-22 inclusive, the forms of projectiles shown are generally similar in construction and similar :in operation to those -hereinbefore described but differ -in that dual propellants are used which may or may not be :explosives. As seen 'in Figures -18 =and 19, the inner'sur- :face of the projectile body 115 isbroached -to provide a multiplicity of slots 150 therein.

;A short agitator'126 is mounted between a plug 151 separating the fuel chamber from the nose adaptorand .aremovable end wall 152 of an inner cylinder 153 which forms :the oxidizerchamber 154. The outer surface of the cylinder "153 is provided with a pair o'fdiametrically opposedsplines which seat in two of the broached slots --15.0;so :as rotate with the projectile.

The .inner surface of the cylinder is provided with :xangularly spaced slots 1551inwhich the' blade edges ofan tag'itator. 166 are seated. The -:'left or rearcnd of the soxidizer chamber 154 is closed by a metering nozzle 156.'haVing-.metering passageways 134 :anda-filler plug "157 .Iforysealing the oxidizer which may be nitric acid. in the chamber 154. The fuel in the fuel chamber may :be aniline .oilvfurfural alcohol, ..or ethyl alcohol which is delivered '10 :the combustion chamber .of the rocket motor 123 by :the 'zbroached slots. 150. These .and the metering passageways 134 :are, sealing disc 124.

The :projectiles :disclosed :in Figures 20, 21 and '22.,are =respectively sthe ;same as the mono-propellant projectiles of Figures 13, 14 and 16 modified for use with dual tpropellants. It will be .apparent in. the operation of the latter thatzgassoonras rthe fusible-sealing disc 124 hasbeen melted, :centrifugal pressure :of "the rotating projectile will .cause'oxidizer to be'metered through the passageways 134 and fuel to be meteredthroughthe slots 150. IF-he .ltwo treact-simultaneouslyiupon contact to "burn at a zprcdeterminedpressure to furnish the-rocket assist power.

Thus, whether :a mono-propellant or a dua'l propellant :used, "the terminal velocity, range and striking force of 'ihe projectile :is tremendously increased with an atgtendant material reduction in :gun barrel-wear.

:It: is to .be-understood that the forms of :the invention herewith shown and described are to be taken as a -;preferred exampleofthe sameand-th'at various changes :in the shape, :size and arrangement :of parts may be :Iesorted to without :departing from the spirit of the inventionor the scopeof the subjoinedclaims.

-We claim:

:1. 1A projectile .adapted to be fir'ed from -a rifled gun .Ebarrel 'by.za conventional tpropellent charge therein com- :prising :a ".tubular casing including a fuel chamber hav- -ting fuel therein :and a :rocket combustion'chamber inrcludingsanditerminating in :ajet nozzle, a powder charge linzsaidi'combustion'cchamber adapted to be --ignited*bythe firing of the gun, a metering nozzle including .fuel massages separating said fuel chamber and said combustion. chamber, and :a fusible :disc :adjacentsaid-powder :charge-and sealing saidpassagesand adaptedto'me'ltupon burning of said powder :charge to :admit "fuel under cen- 'd u ally adeveltJPedpressure' by projectile rotation to said mf zcourse, sealed by the fusible terminating in ajet combustion chamber to furnish thrust to the projectile.

2. A device as recitedKin'claim I wherein-the fuel explosive upon "high velocity impact of the-projectile to form a war head of said fuel'chamber.

A device as recited in claim-'2'whereinsaid fuel passages permit :burriing fuel in said combustion chamber *topass through said passages to 5 ignite :unexpended fuel in said :fuel chamber upon'thetuncovering of the fuel passages 'bythe expending 1 of fuel.

4. A device as -recited in claim 2 wherein said combustion chamber also terminates in a plurality-of jet "nozzles smaller than and concentrically-arranged with said first mentioned jet nozzle and obliquely thereto to furnish rotational velocity to said projectile.

5. A device as recited'in claim 2 wherein said'fuel chamber is closed at one end by a-thin walled chamber having a detonator therein.

6. A device as recited inclaim 5 wherein an agitator including blades is mounted in said fuel chamber to Jim- -part rotation to the fuel upon rotation of the projectile and said blades are'spacedfromsaid thin walled chamber to permit free contact of the explosive-fuel therewith.

'7. A :device as recited in claim 1 wherein said fuel passages permit burning fuel in-said combustion chamber to pass throughsaid passages -to ignite unexpended'fue'l in said fuel chamber upon the uncovering of the 'fuel passages by the-expendingof fuel. 8. A device -as :recited -'-in claim '1 whereimsaid-combustion chamber also terminates in a plurality of jet nozzlessmaller than and concentrically arranged with said first mentioned jet nozzle and obliquely -thereto to "furnish rotational velocity to said projectile.

9. A device as recited inclaim 1 wherein an-agitator including blades is mounted in said fuel chamber to impart rotationto the fuel upon rotation of the projectile.

10. A device as recited in-claim 9-wherein said blades iinclude ports to permit free communication of the fuel within said fuel chamber. I

11. A device as recited 'in claim 9 wherein the ends "of saidblades are-spaced from said *fuel passages topermit freeaccess of the fuel'thereto.

'12. A device 'as recitedin claim 1 wherein said rocket combustion chamber has a press fit with 'said' tubular casing and includes a peripheral groove engageable by a multiwpoint stake on the-inner surface of said casing.

13. A device as recited inclaim 1 wherein saidmetering nozzle has a press *fit with said tubular casing and includes a peripheral groove-engageable by a multi -point stake on the inner surface of said casing.

14. A device as recited in claim 1 wherein said-fusi ble disc is clamped :against the .face of said --metering nozzle bytheforward end of i said combustion chamber.

15. A projectile adapted -to be fired from a gun barrel E'bya conventional propellent charge therein comprising a tubular casing including a fuel chamber having fuel therein and a rocket combustion chamber-including and nozzle, a powder chargein said rocket and means comprising a metering nozzle and seal therefor adapted to melt upon firing of chamber, a fusible "said powder charge to admit fuel to and ignite it in said combustion Chambertocifect propulsionof-the projectile.

Referen es .Cite .in the pfile of this patent .UNITED STATES PATENTS 

